Ceramic granules have been applied to asphaltic shingles for decades to protect the asphalt below from deterioration by ultraviolet (UV) radiation and direct exposure to the elements. While ceramic granules have been successful, and are considered architecturally attractive, they nevertheless suffer from various shortcomings. For example, ceramic granules have become increasingly more expensive over the years and the distribution, handling, and application of ceramic granules can be a significant portion of the cost of manufacturing an asphaltic shingle. Further, ceramic granules tend to become loose and fall off of their shingles over time, which gradually exposes more of the asphalt to the environment thus hastening deterioration of the shingle. Also, applying granules to an asphalt coated substrate during manufacture requires large sophisticated machinery to drop the granules onto the asphalt as it moves along a processing path. This requirement can limit the speed of production and it can be difficult to obtain granule patterns on the substrate with sharp well defined edges.
In addition to the exposed portion of a shingle, various fines such as fine sand commonly is applied to the backs of asphalt shingles to prevent the shingles from sticking together when packaged together in a shingle bundle. This too can be a tedious process during manufacture and fines are not always completely successful for their intended purpose.
There is a need for a asphalt-based shingle having a protective layer that protects the asphalt below from deterioration by the elements for extended periods of time, that does not gradually fall off of the shingles, that is simpler and more precise to apply during fabrication, that is more efficient to manufacture and distribute, and that mimics the architectural appearance of traditional granule coated shingles on a roof, or projects completely new aesthetics. There also is a need for a coating other than sand or other fines on the backs of shingles to prevent them from sticking together. It is to the provision of a shingle and method that meets these and other needs and that exhibits advantages not possible with granules and fines that the present invention is primarily directed.